1. Field of the Invention
The present invention relates generally to an object detection device and a sensing apparatus and, more particularly, to an object detection device for detecting an object and a sensing apparatus including the object detection device.
2. Description of the Related Art
Object detection devices that detect presence/absence of an object and distance to the object have been actively developed in recent years.
For instance, Japanese Patent No. 5251858 discloses a laser radar device including a laser light emitting unit that emits laser light, an optical detection unit that, when laser light is emitted from the laser light emitting unit, detects reflected light which is the laser light reflected off a detection object, a pivoting deflection unit that includes a deflection unit pivotable about a predetermined center axis and that causes the deflection unit to deflect the laser light toward space via a window and deflect the reflected light having passed through the window toward the optical detection unit, a drive unit that drives the pivoting deflection unit, and a distance measurement unit that obtains the distance to the detection object based on detection time, which is time from when the laser light is emitted from the laser emitting unit to when the reflected light reflected off the detection object is detected by the optical detection unit.
Japanese Laid-open Patent Publication No. 2009-063339 discloses a scanning distance measurement apparatus including a first deflecting member that deflects measurement light output from a light emitting unit toward measurement target space, a light receiving lens that condenses reflected light from a measurement target object present in the measurement target space, an optical system that deflects the reflected light having passed through the light receiving lens toward a light receiving unit arranged to face the light emitting unit, and a scanning mechanism that causes the optical system to rotate about a predetermined axial center. The scanning distance measurement apparatus obtains the distance to the measurement target object based on the measurement light and the reflected light detected by the light receiving unit.
Japanese Laid-open Patent Publication No. 2012-107984 discloses a distance measurement apparatus including a light emitting unit that emits a lightwave, a light receiving unit that receives reflected light, which is the lightwave emitted from the light emitting unit and reflected off an object, and delivers an output that depends on intensity of the reflected light, and a distance calculation unit that calculates the distance to the object from which the lightwave is reflected based on the output of the light receiving unit.
Japanese Patent No. 5082704 discloses a laser radar device including a laser light emitting unit that emits laser light, an optical detection unit that, when laser light is emitted from the laser light emitting unit reflected off a detection object, a pivoting deflection unit that includes one deflection unit pivotable about a given center axis and causes the deflection unit to deflect the laser light toward space and deflect the reflected light toward the optical detection unit, a mirror that deflects the laser light emitted from the laser light emitting unit toward the deflection unit, a drive unit that drives the deflection unit of the pivoting deflection unit to rotate, a first rotating unit that rotates the laser light emitting unit about a first rotation axis, a second rotating unit that rotates the laser light emitting unit about a second rotation axis that is orthogonal to the first rotation axis, and a control unit that controls the first rotating unit and the second rotating unit.
However, it is difficult to achieve cost reduction in the apparatuses disclosed in Japanese Patent No. 5251858, Japanese Laid-open Patent Publication No. 2009-063339, Japanese Laid-open Patent Publication No. 2012-107984, and Japanese Patent No. 5082704.